1 /* 2 ******************************************************************************* 3 * Copyright (C) 2007-2013, International Business Machines Corporation and 4 * others. All Rights Reserved. 5 ******************************************************************************* 6 */ 7 #ifndef BASICTZ_H 8 #define BASICTZ_H 9 10 /** 11 * \file 12 * \brief C++ API: ICU TimeZone base class 13 */ 14 15 #include "unicode/utypes.h" 16 17 #if !UCONFIG_NO_FORMATTING 18 19 #include "unicode/timezone.h" 20 #include "unicode/tzrule.h" 21 #include "unicode/tztrans.h" 22 23 U_NAMESPACE_BEGIN 24 25 // forward declarations 26 class UVector; 27 28 /** 29 * <code>BasicTimeZone</code> is an abstract class extending <code>TimeZone</code>. 30 * This class provides some additional methods to access time zone transitions and rules. 31 * All ICU <code>TimeZone</code> concrete subclasses extend this class. 32 * @stable ICU 3.8 33 */ 34 class U_I18N_API BasicTimeZone: public TimeZone { 35 public: 36 /** 37 * Destructor. 38 * @stable ICU 3.8 39 */ 40 virtual ~BasicTimeZone(); 41 42 /** 43 * Gets the first time zone transition after the base time. 44 * @param base The base time. 45 * @param inclusive Whether the base time is inclusive or not. 46 * @param result Receives the first transition after the base time. 47 * @return TRUE if the transition is found. 48 * @stable ICU 3.8 49 */ 50 virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const = 0; 51 52 /** 53 * Gets the most recent time zone transition before the base time. 54 * @param base The base time. 55 * @param inclusive Whether the base time is inclusive or not. 56 * @param result Receives the most recent transition before the base time. 57 * @return TRUE if the transition is found. 58 * @stable ICU 3.8 59 */ 60 virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const = 0; 61 62 /** 63 * Checks if the time zone has equivalent transitions in the time range. 64 * This method returns true when all of transition times, from/to standard 65 * offsets and DST savings used by this time zone match the other in the 66 * time range. 67 * @param tz The <code>BasicTimeZone</code> object to be compared with. 68 * @param start The start time of the evaluated time range (inclusive) 69 * @param end The end time of the evaluated time range (inclusive) 70 * @param ignoreDstAmount 71 * When true, any transitions with only daylight saving amount 72 * changes will be ignored, except either of them is zero. 73 * For example, a transition from rawoffset 3:00/dstsavings 1:00 74 * to rawoffset 2:00/dstsavings 2:00 is excluded from the comparison, 75 * but a transtion from rawoffset 2:00/dstsavings 1:00 to 76 * rawoffset 3:00/dstsavings 0:00 is included. 77 * @param ec Output param to filled in with a success or an error. 78 * @return true if the other time zone has the equivalent transitions in the 79 * time range. 80 * @stable ICU 3.8 81 */ 82 virtual UBool hasEquivalentTransitions(const BasicTimeZone& tz, UDate start, UDate end, 83 UBool ignoreDstAmount, UErrorCode& ec) const; 84 85 /** 86 * Returns the number of <code>TimeZoneRule</code>s which represents time transitions, 87 * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except 88 * <code>InitialTimeZoneRule</code>. The return value range is 0 or any positive value. 89 * @param status Receives error status code. 90 * @return The number of <code>TimeZoneRule</code>s representing time transitions. 91 * @stable ICU 3.8 92 */ 93 virtual int32_t countTransitionRules(UErrorCode& status) const = 0; 94 95 /** 96 * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code> 97 * which represent time transitions for this time zone. On successful return, 98 * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and 99 * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code> 100 * instances up to the size specified by trscount. The results are referencing the 101 * rule instance held by this time zone instance. Therefore, after this time zone 102 * is destructed, they are no longer available. 103 * @param initial Receives the initial timezone rule 104 * @param trsrules Receives the timezone transition rules 105 * @param trscount On input, specify the size of the array 'transitions' receiving 106 * the timezone transition rules. On output, actual number of 107 * rules filled in the array will be set. 108 * @param status Receives error status code. 109 * @stable ICU 3.8 110 */ 111 virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial, 112 const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) const = 0; 113 114 /** 115 * Gets the set of time zone rules valid at the specified time. Some known external time zone 116 * implementations are not capable to handle historic time zone rule changes. Also some 117 * implementations can only handle certain type of rule definitions. 118 * If this time zone does not use any daylight saving time within about 1 year from the specified 119 * time, only the <code>InitialTimeZone</code> is returned. Otherwise, the rule for standard 120 * time and daylight saving time transitions are returned in addition to the 121 * <code>InitialTimeZoneRule</code>. The standard and daylight saving time transition rules are 122 * represented by <code>AnnualTimeZoneRule</code> with <code>DateTimeRule::DOW</code> for its date 123 * rule and <code>DateTimeRule::WALL_TIME</code> for its time rule. Because daylight saving time 124 * rule is changing time to time in many time zones and also mapping a transition time rule to 125 * different type is lossy transformation, the set of rules returned by this method may be valid 126 * for short period of time. 127 * The time zone rule objects returned by this method is owned by the caller, so the caller is 128 * responsible for deleting them after use. 129 * @param date The date used for extracting time zone rules. 130 * @param initial Receives the <code>InitialTimeZone</code>, always not NULL. 131 * @param std Receives the <code>AnnualTimeZoneRule</code> for standard time transitions. 132 * When this time time zone does not observe daylight saving times around the 133 * specified date, NULL is set. 134 * @param dst Receives the <code>AnnualTimeZoneRule</code> for daylight saving time 135 * transitions. When this time zone does not observer daylight saving times 136 * around the specified date, NULL is set. 137 * @param status Receives error status code. 138 * @stable ICU 3.8 139 */ 140 virtual void getSimpleRulesNear(UDate date, InitialTimeZoneRule*& initial, 141 AnnualTimeZoneRule*& std, AnnualTimeZoneRule*& dst, UErrorCode& status) const; 142 143 144 #ifndef U_HIDE_INTERNAL_API 145 /** 146 * The time type option bit flags used by getOffsetFromLocal 147 * @internal 148 */ 149 enum { 150 kStandard = 0x01, 151 kDaylight = 0x03, 152 kFormer = 0x04, 153 kLatter = 0x0C 154 }; 155 #endif /* U_HIDE_INTERNAL_API */ 156 157 /** 158 * Get time zone offsets from local wall time. 159 * @internal 160 */ 161 virtual void getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt, 162 int32_t& rawOffset, int32_t& dstOffset, UErrorCode& status) const; 163 164 protected: 165 166 #ifndef U_HIDE_INTERNAL_API 167 /** 168 * The time type option bit masks used by getOffsetFromLocal 169 * @internal 170 */ 171 enum { 172 kStdDstMask = kDaylight, 173 kFormerLatterMask = kLatter 174 }; 175 #endif /* U_HIDE_INTERNAL_API */ 176 177 /** 178 * Default constructor. 179 * @stable ICU 3.8 180 */ 181 BasicTimeZone(); 182 183 /** 184 * Construct a timezone with a given ID. 185 * @param id a system time zone ID 186 * @stable ICU 3.8 187 */ 188 BasicTimeZone(const UnicodeString &id); 189 190 /** 191 * Copy constructor. 192 * @param source the object to be copied. 193 * @stable ICU 3.8 194 */ 195 BasicTimeZone(const BasicTimeZone& source); 196 197 /** 198 * Gets the set of TimeZoneRule instances applicable to the specified time and after. 199 * @param start The start date used for extracting time zone rules 200 * @param initial Receives the InitialTimeZone, always not NULL 201 * @param transitionRules Receives the transition rules, could be NULL 202 * @param status Receives error status code 203 */ 204 void getTimeZoneRulesAfter(UDate start, InitialTimeZoneRule*& initial, UVector*& transitionRules, 205 UErrorCode& status) const; 206 }; 207 208 U_NAMESPACE_END 209 210 #endif /* #if !UCONFIG_NO_FORMATTING */ 211 212 #endif // BASICTZ_H 213 214 //eof 215
